Clean water for a young Philadelphia

Thomas Birch, Fairmount Water Works, 1821, 布面油畫, 51.1 X 76.3 厘米 (Pennsylvania Academy of the Fine Arts), a Seeing America video

揚聲器: 博士. Anna O. Marley, Curator of Historical American Art, Pennsylvania Academy of the Fine Arts and Dr. 史蒂文糖